Sorry to see that Mathys Your alloys are one of the best Iv seen, IMO keep same alloys & tyres did look a bit stretched before. IMO I would go 285 on rear (IIRC your rears are 10 inch width alloy).
As H5 said House of Kolors is one of the best, most customcar outfits in US use them. There are many differing types of Mettakic blacks so I would take my time & choose. What about a dark charcoal grey-black mettalic?
Central 20 is very subtle & one of the most flowing with existing lines of car IMO.